1. Field of the Invention
The present invention relates to a form pan of the reusable type for use in a form structure.
2. Description of Prior Art
Various types of form pans have been provided for supporting and shaping concrete slab structures, such as, flooring or wall structures. The most popular adapted system is to utilize a form support structure having adjustable posts to support main beams on which a floor, normally constructed of plywood type, lumber or planks, is built to cover the entire area of a floor to be poured. On top of this floor (false work) form pans reinforcement, and concrete is placed. In certain systems, form pans may be used to provide a decorative effect to the ceiling and also too economize on the concrete and reinforcing steel required. In certain structures, the pans are left into the concrete and form a part of the decorative effect and structure of the poured concrete slabs. Other types of pans are utilized for forming only and are removable after the concrete slab has been poured and the concrete has set. The present invention is concerned with this latter type of form pan.
Known form pans of the removable type, are used primarily for shaping concrete surfaces and in most instances, a floor (false work) as above described is required to support the pans and also to provide attachment for the pans. Of the types of form pans known which do not use flooring (false work), the use of a continuous support under the joints of the pans is required, thus constituting a complex support framework which is time consuming to erect and dismantle, making it extremely costly from a labour and material point of view. Still further, when these type forms are removed and in view of the support structure utilized, the concrete surfaces are poorly finished leaving protruding concrete ridges which require further labour to remove or else, the use of additional material to cover up.
The form pan structures heretofore known have many disadvantages, in that some pans require to be assembled individually on the site, or are very difficult to align in a complete system. There are basically two types of pans, and namely, those constructed of metal and those constructed of plastics. The metal ones have the disadvantage of being heavy, difficult to manipulate and install and costly. These type forms are also subject to corrosion. Those constructed of plastics are not sufficiently durable. Also, the known type forms do not interlock with one another, whereby to provide better alignment of the pans on a large surface. Also, known type forms are of short lengths, two to three feet and need complex support structures. Further, these are difficult to remove after concrete has set. Still further, such forms are not easily adaptable in vertical form work.